1. Field of the Invention
The present invention generally relates to curing concrete. More particularly, the present invention relates to a portable system and method for automatically and periodically applying moisture to concrete to ensure proper curing of the concrete. The present invention is portable and can be used with concrete columns, walls, floors, and other concrete items.
2. Description of the Related Art
Concrete typically results from mixing various ingredients including cement, sand, and water. In order to obtain concrete with the most desirable characteristics, concrete must be kept moist for a sufficient period of time after mixing its ingredients. This process is known as curing or hydration. If cured properly, the strength and durability of concrete can be significantly increased since a water-tight concrete substance can be produced. Water-tight concrete is less likely to fracture upon application of a given force than concrete with air pockets and other imperfections. The desired curing period for concrete typically ranges from a few days to several weeks. During this time, appropriate moisture conditions should be continuously maintained throughout the concrete substance.
One method of curing concrete is by use of a concrete curing blanket. A curing blanket typically comprises a large burlap blanket, often in ten feet by forty feet pieces, covered with a plastic material. The curing blanket is placed on the recently mixed concrete and the burlap side of the blanket, which is in contact with the concrete, is periodically wetted in order to maintain moisture on the surface of the concrete. The curing blanket can require rewetting every six to eight hours or less depending on ambient weather conditions. As a result, the curing blanket typically must be rewetted many times during the curing period.
In order to rewet the curing blanket, workers typically use a large hose, connected to a water source, to spray the burlap portion on the underside of the blanket. A gas powered pump is often required in order to provide sufficient water pressure to the large hose. This process requires significant manual labor since the curing blanket must be physically lifted to access the burlap underside and since rewetting, in some cases, may be necessary hourly. In addition, workers often must use a large and heavy hose, similar to a fireman's hose, to spray the curing blanket. The hose discharges substantial amounts of water and therefore a significant amount of water does not reach the curing blanket and ends up on the ground or elsewhere. As a result, this process can waste a significant amount of water and result in a messy work site condition. Another disadvantage is that the cost and labor required to rewet the curing blanket may be significant. In addition, since this process relies on manual labor, error is possible since a worker may forget to rewet the curing blanket or may wet the blanket with too much or not enough water. Human error can result in significant monetary and temporal consequences. According to certain government regulations, if a worker forgets to spray the curing blanket and the concrete structure does not pass certain inspections, then the concrete structure may have to be rebuilt completely resulting in a loss of time and money for the builder.
Another method used to cure concrete is by placing wet concrete in an enclosed curing room for the entire curing period. However, this method has significant limitations. The curing room is not portable and therefore cannot house concrete items commonly developed at a construction site such as concrete columns, a concrete wall, or a large concrete floor. In addition, human error is a problem since this method relies on human involvement in turning the watering device on and off.
Therefore, systems and methods for automatically applying moisture during the curing period with minimal human involvement are desired. In addition, portable, automatic, curing systems and methods that may be transported to a construction or other work site where large, heavy concrete structures are to be cured are desired.